Why shouldn't you use an svg file as a website?

I'm helping some people without much coding experience make websites using Inkscape. They are creating elements and using small bits of Javascript to animate interactions between them on mouse clicks. So far, they have been saving these as .svg files and opening them in their browsers to test them. They are now at the point where they want to put them on the web. I did some tests with GitHub pages, and it looks like if you upload these SVG files you can interact with them just like you could if you opened them in a browser locally.

Is there anything wrong with putting them on the web in this way? If I were doing it myself, I would at least put the SVG image in an html page, as this would provide much more flexibility. However, in this case, the goal is to keep everything as simple as possible. So if I can avoid teaching them HTML right now, so much the better. But the fact that I've never encountered a website that was literally just an svg file makes me worry that there's a serious problem other than the lack of flexibility in making improvements to the website. Does anyone know of one?